The steaming pile that is Precise with kernel 3.2

I don't know if it is a mainline kernel problem but I can tell you that on Ubuntu Precise, Linux kernel 3.2 is a disaster for PostgreSQL. I am not even going to go into a huge rant about it. I am just posting the numbers. See for yourself. There should be a public service announcement about it.

before upgrade to 3.9

08:35:01 AM     CPU     %user     %nice   %system   %iowait    %steal     %idle
08:45:01 AM     all     30.91      0.00      5.66     40.05      0.00     23.38
08:55:02 AM     all     29.32      0.00      5.10     39.66      0.00     25.92
09:05:02 AM     all     31.71      0.00      6.24     40.99      0.00     21.06
09:15:01 AM     all     32.45      0.00      6.59     46.74      0.00     14.21
09:25:01 AM     all     20.62      0.00      5.39     60.00      0.00     14.00
09:35:01 AM     all     31.03      0.00      3.61     33.95      0.00     31.41
09:45:01 AM     all     36.54      0.00      3.22     34.13      0.00     26.11
09:55:02 AM     all     40.17      0.00      3.66     30.98      0.00     25.19
10:05:01 AM     all     33.49      0.00      3.04     32.28      0.00     31.19
10:15:01 AM     all     48.63      0.00      2.87     25.50      0.00     23.00
10:25:01 AM     all     51.34      0.00      3.56     26.06      0.00     19.04
10:35:01 AM     all     39.41      0.00      3.44     29.86      0.00     27.29
10:45:02 AM     all     36.07      0.00      8.79     30.94      0.00     24.20
10:55:03 AM     all     38.04      0.00      7.98     32.98      0.00     21.01
11:05:11 AM     all     39.25      0.00      8.81     36.75      0.00     15.19
11:15:02 AM     all     35.19      0.00      8.76     41.98      0.00     14.07
11:25:03 AM     all     38.21      0.00      9.65     38.86      0.00     13.28
11:35:02 AM     all     42.92      0.00     11.66     34.28      0.00     11.14
11:45:02 AM     all     39.40      0.00      9.96     39.03      0.00     11.61
11:55:01 AM     all     28.72      0.00      3.27     36.32      0.00     31.69

after upgrade to 3.9

                CPU     %user     %nice   %system   %iowait    %steal     %idle
08:35:02 AM     all     40.08      0.00      4.46     10.66      0.00     44.80
08:45:01 AM     all     38.80      0.00      3.94      7.96      0.00     49.29
08:55:01 AM     all     31.48      0.00      3.03      2.58      0.00     62.91
09:05:01 AM     all     32.18      0.00      3.09      3.86      0.00     60.87
09:15:01 AM     all     26.71      0.00      2.39      3.52      0.00     67.39
09:25:01 AM     all     30.49      0.00      3.10      2.80      0.00     63.61
09:35:01 AM     all     32.50      0.00      3.49      3.42      0.00     60.60
09:45:01 AM     all     36.76      0.00      3.85      6.39      0.00     53.01
09:55:01 AM     all     44.45      0.00      4.63      9.23      0.00     41.69
10:05:02 AM     all     38.39      0.00      4.28      8.60      0.00     48.72
10:15:01 AM     all     33.57      0.00      3.53      4.10      0.00     58.80
10:25:01 AM     all     29.42      0.00      2.96      3.16      0.00     64.45
10:35:01 AM     all     32.90      0.00      3.37      5.33      0.00     58.40
10:45:01 AM     all     34.56      0.00      3.62      4.32      0.00     57.50
10:55:01 AM     all     34.84      0.00      3.37      4.27      0.00     57.52
11:05:02 AM     all     38.30      0.00      4.05      7.56      0.00     50.08
11:15:01 AM     all     36.80      0.00      3.54      9.51      0.00     50.16
11:25:01 AM     all     34.79      0.00      3.82      8.17      0.00     53.21
11:35:01 AM     all     32.68      0.00      3.07      4.97      0.00     59.28
11:45:02 AM     all     31.77      0.00      3.45      6.07      0.00     58.72
11:55:01 AM    all     33.58      0.00      3.92      6.39      0.00     56.10